This is represent about the equity in undistributed earning of subsidiaries.

No definition available.

Name:	cmoh_EquityInUndistributedEarningOfSubsidiries
Namespace Prefix:	cmoh_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Proceeds from issuance of common stock for deferred compensation plan.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Proceeds from issuance of common stock option plan

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

The net change between the beginning and ending balance of cash and cash equivalents and also the amount outstanding of funds lent to other depository institutions, securities brokers, or securities dealers in the form of Federal Funds sold.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The cash inflow associated with issuance of treasury stock under stock option plan during the period.

+ References

No definition available.

+ Details

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- Definition

The sum of cash and cash equivalents plus Federal Funds Sold. Cash and cash equivalents consist of short term, highly liquid investments that are readily convertible to known amounts of cash and are so near their maturity that they present negligible risk of changes in value due to changes in interest rates -- usually with an original maturity less than 90 days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.1,2,3)

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Period Type:	instant

- Definition

Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 24

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3521-108585

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-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 26

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3574-108585

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- Definition

Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

+ References

+ Details

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- Definition

Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

+ References

+ Details

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Net Income

-URI http://asc.fasb.org/extlink&oid=6518256

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.19)

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.18)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.22)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 19

-Article 5

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 20

-Article 9

+ Details

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- Definition

Other cash or noncash adjustments to reconcile net income to cash provided by (used in) operating activities that are not separately disclosed in the statement of cash flows (for example, cash received or cash paid during the current period for miscellaneous operating activities, net change during the reporting period in other assets or other liabilities).

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The total cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards, including stock option exercises. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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PARENT CORPORATION STATEMENTS (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 813us-gaap_NetIncomeLoss	$ 859us-gaap_NetIncomeLoss	$ 865us-gaap_NetIncomeLoss	$ 759us-gaap_NetIncomeLoss	$ 805us-gaap_NetIncomeLoss	$ 792us-gaap_NetIncomeLoss	$ 773us-gaap_NetIncomeLoss	$ 685us-gaap_NetIncomeLoss	$ 3,296us-gaap_NetIncomeLoss	$ 3,055us-gaap_NetIncomeLoss	$ 2,938us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash from operating activities
Stock-based compensation									127us-gaap_ShareBasedCompensation	96us-gaap_ShareBasedCompensation	71us-gaap_ShareBasedCompensation
CASH FLOWS FROM FINANCING ACTIVITIES
Treasury stock issued for deferred compensation plan									61	69	83
Treasury stock issued under stock option plans									33	12	6
Common stock issued for deferred compensation plan									40	0	0
Common stock issued for stock option plans									12	0	0
Cash dividends paid									(843)us-gaap_PaymentsOfDividendsCommonStock	(718)us-gaap_PaymentsOfDividendsCommonStock	(601)us-gaap_PaymentsOfDividendsCommonStock
Net change in cash									9,032	(4,785)	12,181
Cash equivalents and federal funds sold at beginning of year				18,119				22,904	18,119	22,904	10,723
Cash equivalents and federal funds sold at end of year	27,151				18,119				27,151	18,119	22,904
Parent Company [Member]
CASH FLOWS FROM OPERATING ACTIVITIES
Net income									3,296	3,055	2,938
Adjustments to reconcile net income to net cash from operating activities
Equity in undistributed earnings of subsidiaries									(2,548)	(2,428)	(2,421)
Stock-based compensation									127	96	71
Other									(20)	(39)	(38)
Net cash from operating activities									855	684	550
CASH FLOWS FROM INVESTING ACTIVITIES
Net cash from investing activities									0	0	0
CASH FLOWS FROM FINANCING ACTIVITIES
Treasury stock issued for deferred compensation plan									61	69	83
Treasury stock issued under stock option plans									33	12	6
Common stock issued for deferred compensation plan									40	0	0
Common stock issued for stock option plans									12	0	0
Cash dividends paid									(843)	(718)	(601)
Net cash from financing activities									(697)	(637)	(512)
Net change in cash									158	47	38
Cash equivalents and federal funds sold at beginning of year				249				202	249	202	164
Cash equivalents and federal funds sold at end of year	$ 407				$ 249				$ 407	$ 249	$ 202